Atomic Structure and the Periodic Table Flashcards

Question

solution

Answer 1

a solute dissolved in a solvent

Answer 2

a substance that will dissolve

Answer 3

a substance that will not dissolve

Answer 4

the solid that dissolves in a solvent

Answer 5

separates insoluble solids from liquids

Answer 6

separate soluble solids from solutions -pour solution into evaporating dish -slows heat the solution - the solvent will evaporate and the solution will get more concentrated. eventually crystals will start to form. - keep heating the evaporating dish until all you have left are dry crystals can only be used if the salt doesn't decompose (break down) when heated

Answer 7

separate soluble solids from solutions - pour solution into evaporating dish and gently heat - some of the solvent will evaporate and the solution will get more concentrated -once some of the solvent has evaporated or you see crystals start to form, remove the dish from the heat and leave the solution to cool -the salt should start to form crystals as it becomes insoluble in the cold, highly concentrated solution -filter the crystals out of the solution and leave them in a warm place to dry

Answer 8

solid spheres plum pudding model nuclear model - Rutherford (alpha particle scattering experiment) nuclear model - Bohr Rutherford - existence of protons James Chadwick - existence of neutrons - model of the atom close to nowadays nuclear model

Answer 9

J J Thomson ball of positive charge with electrons stuck in it

Answer 10

Rutherford tiny, positively charged nucleus at the centre, where most of the mass is concentrated. A 'cloud' of negative electrons surround the nucleus - most of the atom is empty space -conducted alpha particle scattering experiments -fired positively charged alpha particles at an extremely thin sheet of gold-expected to pass straight through the sheet or be slightly deflected at most -when alpha particles came near the concentrated, positive charge of the nucleus, they were deflected - if they were fired directly at the nucleus, they were deflected backwards -otherwise, they passed through the empty space

Answer 11

scientists realised that electrons in a 'cloud' around the nucleus of an atom, as Rutherford described, would be attracted to the nucleus, causing the atom to collapse suggested that all electrons were contained in shells - electrons orbit the nucleus in fixed shells and aren't anywhere in between - each shell is a fixed distance from the nucleus

Answer 12

chromatography filtration crystallisation simple distillation fractional distillation

Answer 13

used to separate a liquid from a solution -solution is heated, part with lowest boiling point evaporates first -vapour is cooled, condenses, and is collected -rest of solution is left behind in the flask can be used to separate salt and sea water problem is can only be used to separate things with very different boiling points - if the temperature goes higher than the boiling point of the substance with the higher boiling point, they'll mix again

Answer 14

used to separate a mixture of liquids -put mixture in flask and stick a fractionating column on top and heat it -the different liquids have different boiling points - evaporate at different temps -liquid with lowest boiling point evaporates first - when the temp on the thermometer matches the boiling point, it will reach the top of the column -liquids with higher boiling points will start to evaporate, but the column gets cooler towards the top so will only get part of the way before condensing and running back towards the flask -when the first liquid has been collected, you raise the temperature until the next one reaches the top

Answer 15

used to separate different dyes in ink -draw a line in pencil (insoluble and won't dissolve in the solvent) near the bottom of a sheet of filter paper -add a spot of ink to the line and place the sheet in a beaker of solvent e.g. water -make sure your ink isn't touching the solvent otherwise is may dissolve -put a lid on top of the contained to prevent it from evaporating -solvent seeps into the paper, carrying the ink with it -each different dye in the ink will move up the paper at a different rate so will separate out + each will form a spot in a different place -if any of the dye's are insoluble they will stay on the baseline -when the solvent has nearly reached the top of the paper, take the paper out of the beaker and leave it to dry -the end result is a pattern of spots called a chromatogram

Answer 16

their physical and chemical properties their relative atomic mass

Answer 17

left gaps and predicted new elements -mainly in order of atomic mass but switched that order if the properties meant it should be changed -organised elements with similar properties into the same group -gaps were left to make sure that elements with similar properties stayed in the same groups. some indicated undiscovered elements + allowed Mendeleev to predict what their properties might be discovery of isotopes supported this - to not place elements in a strict order of atomic mass but to take account of their properties - isotopes of the same element have different atomic masses but the same chemical properties so occupy the same position on the periodic table

Answer 18

100ish elements elements laid out in order of increasing atomic (proton) number - arranging the elements like this means there are repeating patterns in the properties of the elements metals - left non-metals - right vertical columns - groups. group number tells you how many electrons are in the outer shell rows - periods-each new period represents another full shell of electrons

Answer 19

elements which can form positive ions when they react towards the bottom and left of the periodic table left - don't have many electrons to remove bottom - have outer electrons which are a long way from the nucleus so feel a weaker attraction BOTH of these mean that not much energy is needed to remove the electrons metallic bonding - have similar basic physical properties -strong -malleable -great conductors of heat and electricity -high melting and boiling points

Answer 20

don't generally from positive ions when they react at far right and top of periodic table forming positive ions is much more difficult right - lots of electrons to remove to get a full outer shell top - outer electrons are close to the nucleus so feel a strong attraction far more feasible for them to gain or share electrons to get a full outer shell no metallic bonding -dull looking -brittle -aren't always solids at room temp -don't generally conduct electricity -lower density

Answer 21

between group 2 and 3 centre of the periodic table -typical metals and have the expected properties of metals -they also have: -can have more than one ion -transition metal ions are often coloured -transition metal compounds make good catalysts

Answer 22

the Alkali metals - reactive, soft metals one electron in outer shell - very reactive + gives them similar properties - low density trends as you go DOWN the group: increasing reactivity - outer electron is more easily lost as the attraction between the nucleus and electron decreases, because the electron is further away from the nucleus the further down the group you go lower melting and boiling points higher relative atomic mass only ever react to form ionic compounds with non-metals (transfer of electrons) need little energy to lose an electron and form 1+ ions more reactive than transition metals - more vigorous - much less dense, strong, and hard than transition metals + have lower boiling points

Answer 23

when Group 1 metals are put in water, they react vigorously to produce hydrogen gas and metal hydroxides - compounds that dissolve in water to produce alkaline solutions 2Na (s) + 2H 2 O (l) → 2NaOH (aq) + H 2 (g) sodium + water → sodium hydroxide + hydrogen - the more reactive (lower down the group), the more violent the reaction - amount of energy released by the reaction increases down the group

Answer 24

Group 1 metals react vigorously when heated in chlorine gas to form white metal chloride salts as you go down the group, reactivity increases so the reaction with chlorine gets more vigorous

Answer 25

form a metal oxide - different types will form depending on the Group 1 metal Lithium → lithium oxide Sodium → mixture of sodium oxide and sodium peroxide Potassium → mixture of potassium peroxide and potassium superoxide

Answer 26

Halogens non-metals with coloured vapours as you go DOWN the group: -become less reactive - it's harder to gain an extra electron, because the outer shell's further from the nucleus - have higher melting and boiling points - have higher relative atomic masses can form molecular compounds - can share electrons with other non-metals via covalent bonding to achieve a full outer shell form ionic bonds with metals - 1- ions called halides when they bond with metals more reactive halogens will displace less reactive ones (displacement reaction)

Answer 27

the Noble Gases - inert, colourless gases eight electrons in outer shell (except helium which has 2) - full outer shell - stable - don't react with much at all exist as monatomic gases - single atoms not bonded to each other non-flammable as you go DOWN the group: -boiling point increases - greater number of electrons in each atom leading to greater intermolecular forces between them which need to be overcome